Washington - The gunman who shot dead three police officers and wounded three others in the Louisiana capital of Baton Rouge on Sunday was killed and there are no suspects at large, officials said."We believe the person that shot and killed our officers, that he is a person that was shot and killed at the scene," Louisiana State Police Superintendent Colonel Mike Edmonson told reporters. "What we do not believe is we have any other shooter held up in the Baton Rouge area."CNN reported on Sunday night that the shooter had been identified as Gavin Long. He apparently died in a shoot-out with police on his birthday. He was born, sources told CNN on July 17, 1987.